The present invention generally relates to an image forming apparatus, and more particularly to an image forming apparatus which utilizes an electrophotographic process, such as a laser beam printer, a facsimile machine or a copier.
Currently, an image forming apparatus which utilizes an electrophotographic process, such as a laser beam printer, a facsimile machine or a copier is widely used. Generally, it is required that a user can certainly maintain an image forming apparatus with ease. For example, sometimes, a toner cartridge accommodated in the image forming apparatus must be replaced by a new toner cartridge. A paper jam must be removed with ease by the user. For these requirements, there have been proposed various arrangements of structural elements of an image forming apparatus.
For example, an electrophotographic image forming apparatus having a replaceable optical unit is proposed in U.S. patent application Ser. No. 213,778, the assignee of which is the same as the assignee of this application. However, the proposed electrophotographic image forming apparatus mainly relates to a replaceable optical unit and is not directed to an improvement on other structural elements such as a photosensitive drum and a toner cartridge in order to achieve easy and safety replacement operation.